More on data from teratogen information systems (TIS)

The Risk of Adverse Pregnancy Outcome After First Trimester Exposure to H1 Antihistamines: A Systematic Review and Meta-Analysis

INTRODUCTION

H1 antihistamines are used for the treatment of nausea and vomiting during pregnancy as well as the symptomatic relief of asthma, urticaria, allergy, and the common cold. Although they are overall felt to be safe during pregnancy, recently several studies have challenged this assumption, as millions of women are exposed to them in the first trimester.

METHODS

Following the guidelines of PRISMA, a systematic review was performed to retrieve all published articles involving H1-antihistamine exposure during pregnancy. Electronic databases including PubMed and EMBASE were searched for possibly relevant articles published in any language up to December 2015.

RESULTS

After removing duplicate publications, and excluding animal studies and studies on drug effectiveness, 342 articles were reviewed in detail and 37 studies fulfilled the inclusion criteria for the meta-analysis. In cohort studies, the risk of major malformation in the offspring of women exposed to H1 antihistamines was not higher than that of the control population (OR 1.07; 95% CI 0.98-1.16). The Q-statistic for heterogeneity of effects was not significant (p > 0.05, I ² < 25%) and there was no evidence of publication bias. Similar results were achieved with case-control studies (OR 1.05; 95% CI 0.90-1.23). Similarly, H1 antihistamines were not associated with more spontaneous abortions (OR 1.00; 95% CI 0.83-1.20), prematurity (OR 0.96; 95% CI 0.76-1.20), stillbirth (OR 1.23; 95% CI 0.48-3.18) or low birth weight (OR 1.20; 95% CI 0.63-2.29).

CONCLUSIONS

Based on our meta-analyses, which included a large number of studies, H1 antihistamines are not associated with an increased risk of major malformation or other adverse fetal outcomes. This study provides important information to both pregnant women and their healthcare providers regarding the safety and risk of H1 antihistamine use during this sensitive time.

Angiotensin-II receptor 1 antagonist fetopathy--risk assessment, critical time period and vena cava thrombosis as a possible new feature

AIMS

Angiotensin-II receptor 1 antagonists (AT₁-antagonists) may cause severe and even lethal fetopathy in late pregnancy. However, exposure still occurs in spite of warnings in package leaflets. This study aimed to assess the risk of fetopathy, the sensitive time window, and possible new symptoms in prospective as well as retrospective cases with AT₁-antagonist treatment during the second or third trimester of pregnancy.

METHODS

Patients were enrolled by the Berlin Institute for Clinical Teratology and Drug Risk Assessment in Pregnancy between 1999 and 2011 through risk consultation. Symptoms defined as indicative of AT₁-antagonist fetopathy were: oligo-/anhydramnios, renal insufficiency, lung hypoplasia, joint contractures, skull hypoplasia and fetal/neonatal death.

RESULTS

In 5/29 (17%) prospectively enrolled cases with AT₁-antagonist exposure beyond the first trimester oligo-/anhydramnios was diagnosed. Two infants showed additional symptoms of fetopathy. The risk is more than 30% if treatment continues beyond the 20th week of pregnancy. Oligo-/anhydramnios was reversible after AT₁-antagonist withdrawal. Among 16 retrospective case reports, three infants presented with a thrombosis of the inferior vena cava in the vicinity of the renal veins. Four out of 13 live births did not survive.

CONCLUSIONS

Our survey suggests that the risk increases with duration of AT₁-antagonist treatment into late pregnancy and oligo-/anhydramnios may be reversible after AT₁-antagonist discontinuation. Thrombosis of inferior vena cava may be a new feature of AT₁-antagonist fetopathy. AT₁-antagonist medication during pregnancy constitutes a considerable risk and must be discontinued immediately. In case of indicative diagnostic findings in either the fetus or newborn, previous maternal AT₁-antagonist exposure should be considered.

Atypical antipsychotic drugs and pregnancy outcome: a prospective, cohort study

Women of childbearing age are often affected with psychotic disorders, requiring the use of antipsychotic medication during pregnancy. In the present study, we prospectively followed the pregnancies of 561 women exposed to second-generation antipsychotic agents (SGAs; study cohort) and compared these to 284 pregnant women exposed to first-generation antipsychotic agents (FGAs; comparison cohort I) and to 1122 pregnant women using drugs known as not harmful to the unborn (comparison cohort II). Subjects were enrolled through the Institute's consultation service. Major malformation rates of SGA exposed were higher compared to comparison cohort II (adjusted odds ratio, 2.17; 95% confidence interval, 1.20-3.91), possibly reflecting a detection bias concerning atrial and ventricular septal defects. Postnatal disorders occurred significantly more often in infants prenatally exposed to SGAs (15.6%) and FGAs (21.6%) compared to 4.2% of comparison cohort II. Cumulative incidences of elective terminations of pregnancy were significantly higher in both the study cohort (17%) and comparison cohort I (21%) compared to comparison cohort II (3%), whereas the rates of spontaneous abortions did not differ. The numbers of stillbirths and neonatal deaths were within the reference range. Preterm birth and low birth weight were more common in infants exposed to FGAs. To conclude, our findings did not reveal a major teratogenic risk for SGAs, making the better studied drugs of this group a treatment option during pregnancy. Because neonates exposed to SGAs or FGAs in the last gestational week are at higher risk of postnatal disorders, delivery should be planned in clinics with neonatal intensive care units.

Teratogenicity of mycophenolate confirmed in a prospective study of the European Network of Teratology Information Services

After maternal exposure to mycophenolate in pregnancy a high number of fetal losses and a specific pattern of birth defects consisting of microtia, cleft lip, and other anomalies have been reported. However, so far, prospective data on pregnancy outcome allowing quantitative risk assessment are missing. We report on 57 prospectively ascertained pregnancies after maternal therapy with mycophenolate (mycophenolate mofetil or mycophenolate sodium) identified by European Teratology Information Services (ETIS) through their risk consultation process. The outcome of these prospective pregnancies was as follows: 16 spontaneous abortions, 12 elective terminations of pregnancy (ETOP) (including two late terminations for multiple malformations consistent with mycophenolate embryopathy), and 29 liveborn infants. The probability of spontaneous abortion was about 45% (95% CI 29 to 66%) estimated using survival analysis technique. Six out of 29 live born infants had major congenital defects: Two with external auditory canal atresia (EACA) (with and without microtia), one with tracheo-esophageal atresia, one with severe hydronephrosis, one with an atrial septal defect (ASD) and one with a myelomeningocele. Thus, at least four fetuses/infants of our prospective case series had a clinical phenotype consistent with mycophenolate embryopathy. Our results confirm a high incidence of major malformations (26%) after first trimester exposure to mycophenolate. Apart from exposure to mycophenololate, the underlying maternal disease and concomitant medication may also have contributed to the other poor pregnancy outcomes such as a high rate of spontaneous abortions, prematurity (62%), and low birth weight (31%).

Fetal outcome after technetium scintigraphy in early pregnancy

OBJECTIVE

Occasionally, either for urgent diagnostic reasons or by accident, pregnant women are exposed to technetium scintigraphy, the consequences of which were unknown, due to lack of systematic data. Therefore, clinical data was needed to assess the risk and safety of technetium scintigraphy with respect to prenatal development.

METHODOLOGY

Requests for information with regard to technetium scintigraphy from pregnant women or their physicians were followed by the Berlin Institute for Clinical Teratology. A prospective observational cohort study was performed using data collected between 1991 and 2008. Pregnancy outcome for a cohort of pregnant women exposed to Tc-99m-scintigraphy of thyroid (n=102) or bone (n=20) during pregnancy was compared with a control group without teratogenic exposure (n=366).

RESULTS

Major birth defects were no more common in the study group than in the control group (OR 1.00; 95% CI 0.23-3.38) and no specific pattern of birth defects was found. Spontaneous abortion rate (OR 0.51), preterm deliveries, and birth measurements of newborns were not significantly different from controls.

CONCLUSION

This prospective observational study suggests that the inadvertent exposure to Tc-99m-scintigraphy in early pregnancy is relatively safe for the fetus.

Failure of the emergency contraceptive levonorgestrel and the risk of adverse effects in pregnancy and on fetal development: an observational cohort study

OBJECTIVE

To determine pregnancy and neonatal outcome after the failure of levonorgestrel as an emergency contraceptive.

DESIGN

A retrospective observational cohort study.

SETTING

Telephone consultations concerning reproductive risk factors conducted by Telefono Rosso-Teratology Information Service, Catholic University of Sacred Heart, Rome, Italy.

PATIENT(S)

Women exposed to levonorgestrel (36 cases) compared with a control group (80 cases).

INTERVENTION(S)

Teratological counseling.

MAIN OUTCOME MEASURE(S)

The rate of congenital anomalies, the prepartum or peripartum complications, and the pregnancy outcomes.

RESULT(S)

Twenty-five exposed newborns with length and weight identical to that of the control group were shown to be without increased risk of congenital malformation. No statistical differences were observed in terms of spontaneous or legal abortion and pregnancy and neonatal complications, and there was no ectopic pregnancy in either group.

CONCLUSION(S)

Although the sample size was small, in our experience, the failure of levonorgestrel as an emergency contraceptive was not associated with an increased risk of major congenital malformations, prepartum or peripartum complications, or an adverse pregnancy outcome.

Teratology Information Services in Europe and Their Contribution to the Prevention of Congenital Anomalies

OBJECTIVES

To inform on Teratology Information Services (TIS) in Europe, their history, function and activity in preventing congenital malformations.

CONCLUSIONS

Clinical teratology tries to identify human teratogens. TIS play an important role in public health by providing counsel on known reproductive risks and conducting specific research. This has led to a reduction in unnecessary fears of pregnant women and pregnancy terminations, as well as to better, more appropriate drug selection to treat acute or chronic disease. In addition, TIS units also conduct prospective studies and inform the public and physicians of the possible effects of environmental agents on the developing embryo and fetus.

Selection bias in Teratology Information Service pregnancy outcome studies

BACKGROUND

Pregnancy outcome studies conducted through Teratology Information Services (TIS) rely on volunteer subjects. If these subjects tend to have different risk profiles than the population from which they are drawn, the results of TIS studies may have limited generalizability.

METHODS

We selected all subjects who enrolled in the California Teratogen Information Service (CTIS) pregnancy outcome study for prenatal exposure to carbamazepine or valproic acid between 1990 and 1997 and who received prenatal care through Kaiser Permanente of Southern California (n = 13). We compared these subjects to Kaiser patients identified through the Maternal Serum Alpha Fetoprotein Program with exposure to carbamazepine or valproic acid but who had not enrolled in the CTIS project. The controls were matched by Kaiser location and pregnancy year using a 2:1 ratio (n = 26). Medical records were reviewed and the prevalence of 14 pregnancy risk factors was compared between the two groups.

RESULTS

There were no significant differences between the groups on any one risk factor; however, a notably higher proportion of women who did not enroll in the CTIS study used tobacco or had a positive family history of congenital anomalies.

CONCLUSIONS

Although the sample was small, and results may not apply to other exposures in different health care environments, these data provide some evidence that women who enroll in TIS pregnancy outcome studies do not have a substantially different pregnancy risk profile than women who do not. Efforts to address possible selection bias should be incorporated in future TIS study design.

Pregnancy outcome after gestational exposure to metronidazole: a prospective controlled cohort study

BACKGROUND

Metronidazole is an important antibacterial agent commonly used in women of reproductive age. Its use in pregnancy is a reason for concern for women and their health care providers. The objective was to examine the fetal safety of metronidazole.

METHODS

The Israeli Teratogen Information Service prospectively collected and followed up 228 women exposed to metronidazole in pregnancy, 86.2% of whom with first-trimester exposure. Pregnancy outcome was compared with that of a control group, who were counseled during the same period for nonteratogenic exposure.

RESULTS

There was no difference in the rate of major malformations between the groups (3/190; 1.6% [metronidazole] vs. 8/575; 1.4% [control], P = 0.739). The rate of major malformations did not differ between the groups even after including elective terminations of pregnancy due to prenatally diagnosed malformations (5/192; 2.6% [metronidazole] vs. 12/579; 2.1% [control], P = 0.777). A reduced neonatal birth weight was found in the metronidazole group compared with controls without significant differences in the rate of prematurity or in gestational age at delivery. The mean birth weight was lower in the metronidazole group when comparing the subgroup of term infants.

CONCLUSIONS

This study confirms that metronidazole does not represent a major teratogenic risk in humans when used in the recommended doses.